Adding a Partner / share holder in Freelancer company in Portugal

Tax and legal
1

I have a plan to start a freelancer IT company in portugal .
Can i add any partner or share holder in company say after few months or a year.

I mean from Single-member private limited company incorporation can i convert it to a company where i can hire people and give them job in Portugal

2

Pay big attention to the taxes of portugal. In addition, less developed structures, and a lot of bureaucracy